Re: Everyday Looper - A Looper for the iPhone/iPod Touch

[Raphaël - Mancing Dolecules <raphael@mancingdolecules.com>]

Hi Jesse !!

Thanks for your thoughts about my looper :p. That's really valuable for me, given your experience with SooperLooper :D. Haven't tried out ThumbJam yet, but have seen the videos and the concept seems very well mastered, and it just sounds really good ! Very nice use of sampled instruments.

In fact yes, multiple loop length are on my TODO list. It's planed for long-term as I can foresee all the problems that I'll have to face to make it work well, speaking of both gesture/interaction and tech (non-accurate synchronization being my main fear, even if it's manageable).

For the graphical threading part, there is no official way to thread it, and Apple still recommend to make OpenGL calls on the main loop. Nevertheless it's possible. I've done it on OS 2.2, but it gave me totally inconsistent frame rate, worst than the NSTimer on main thread method, which is already awful ^^. Here comes the 3.1 update and the CADisplayLink add, which can be run on the RunLoop of your choice, so possibly a RunLoop of another thread. This way, I hope the frame rate to stay consistent enough to be usable. I haven't have tried it yet, and no one seems to have on devforums. Mainly because no one seems to be bothered by touch latency with other type of apps.

However I can't be certain that it'll work, because the inconsistent frame rate may not be resolved by CADisplayLink on a non-main thread. If it doesn't work, I'll have to carefully thread the non-OpenGL part of my graphical thread, which is already very minimal, to reduce the graphical mainThread time frame.

Is it a problem you are trying to solve too ? Or do you find the touch latency to be low enough ? I think the mileage may vary between apps as we don't "charge" the mainLoop the same way and we don't necessarily let the mainThread with the highest priority.

Raphaël